| Message ID | 20210105202126.2879650-1-trix@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | cifs: check pointer before freeing | expand |
On Tue, Jan 05, 2021 at 12:21:26PM -0800, trix@redhat.com wrote: > From: Tom Rix <trix@redhat.com> > > clang static analysis reports this problem > > dfs_cache.c:591:2: warning: Argument to kfree() is a constant address > (18446744073709551614), which is not memory allocated by malloc() > kfree(vi); > ^~~~~~~~~ > > In dfs_cache_del_vol() the volume info pointer 'vi' being freed > is the return of a call to find_vol(). The large constant address > is find_vol() returning an error. > > Add an error check to dfs_cache_del_vol() similar to the one done > in dfs_cache_update_vol(). > > Fixes: 54be1f6c1c37 ("cifs: Add DFS cache routines") > Signed-off-by: Tom Rix <trix@redhat.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> > --- > fs/cifs/dfs_cache.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c > index 6ad6ba5f6ebe..0fdb0de7ff86 100644 > --- a/fs/cifs/dfs_cache.c > +++ b/fs/cifs/dfs_cache.c > @@ -1260,7 +1260,8 @@ void dfs_cache_del_vol(const char *fullpath) > vi = find_vol(fullpath); > spin_unlock(&vol_list_lock); > > - kref_put(&vi->refcnt, vol_release); > + if (!IS_ERR(vi)) > + kref_put(&vi->refcnt, vol_release); > } > > /** > -- > 2.27.0 >
merged into cifs-2.6.git for-next and added cc:stable On Tue, Jan 5, 2021 at 5:08 PM Nathan Chancellor <natechancellor@gmail.com> wrote: > > On Tue, Jan 05, 2021 at 12:21:26PM -0800, trix@redhat.com wrote: > > From: Tom Rix <trix@redhat.com> > > > > clang static analysis reports this problem > > > > dfs_cache.c:591:2: warning: Argument to kfree() is a constant address > > (18446744073709551614), which is not memory allocated by malloc() > > kfree(vi); > > ^~~~~~~~~ > > > > In dfs_cache_del_vol() the volume info pointer 'vi' being freed > > is the return of a call to find_vol(). The large constant address > > is find_vol() returning an error. > > > > Add an error check to dfs_cache_del_vol() similar to the one done > > in dfs_cache_update_vol(). > > > > Fixes: 54be1f6c1c37 ("cifs: Add DFS cache routines") > > Signed-off-by: Tom Rix <trix@redhat.com> > > Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> > > > --- > > fs/cifs/dfs_cache.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c > > index 6ad6ba5f6ebe..0fdb0de7ff86 100644 > > --- a/fs/cifs/dfs_cache.c > > +++ b/fs/cifs/dfs_cache.c > > @@ -1260,7 +1260,8 @@ void dfs_cache_del_vol(const char *fullpath) > > vi = find_vol(fullpath); > > spin_unlock(&vol_list_lock); > > > > - kref_put(&vi->refcnt, vol_release); > > + if (!IS_ERR(vi)) > > + kref_put(&vi->refcnt, vol_release); > > } > > > > /** > > -- > > 2.27.0 > >
diff --git a/fs/cifs/dfs_cache.c b/fs/cifs/dfs_cache.c index 6ad6ba5f6ebe..0fdb0de7ff86 100644 --- a/fs/cifs/dfs_cache.c +++ b/fs/cifs/dfs_cache.c @@ -1260,7 +1260,8 @@ void dfs_cache_del_vol(const char *fullpath) vi = find_vol(fullpath); spin_unlock(&vol_list_lock); - kref_put(&vi->refcnt, vol_release); + if (!IS_ERR(vi)) + kref_put(&vi->refcnt, vol_release); } /**